Is there ANY way to do arbitrary column selection without the need to constantly hold the right mouse button when selecting columns? I find it very tiring and annoying.

Here's how Notepad++ does it: place cursor at the starting point, hold Alt+Shift, click at the ending point. Voila, block selection done! The benefit of this is that you can select over a very large amount of rows without holding the right mouse button and scrolling the mousewheel (carpal tunnel syndrome, here I come), and just using keyboard shortcuts is too slow.

That's not it - that draws a marquee, so I have to hold the middle mouse button. The point that I was trying to show in the GIF is to draw a block selection WITHOUT holding any mouse buttons - just holding a modifier and two mouse clicks on starting and ending points.

Unless someone gets interested in updating the plugin, the default behaviour in Sublime won't get you what you want.

I agree that it's less than ideal; in fact Sublime's modeless selection is less than ideal in a number of cases. Example, there's no line selection, which makes CnP groups of lines around irritating because paste behaviour depends on where the cursor is placed horizontally. On the flipside, that's a design choice that Jon's made for the rich multicursor/multiselect model which has other advantages.

Personally I think that proper column and line selection modes could be incorporated into Sublime's multi-cursor model, though some sanity would be needed especially with multi-column selection. Then there's the issue of keeping the interface (key and mouse-bindings) logical and intuitive. I can see why Jon's avoided it, but there is a case for doing it. As is the case for a number of other oft-asked features: virtual whitespace, variable tabstops, progress and interuption on UI blocking ops, proper macros, better linewrap behaviour for non-programming tasks, graceful handling of long lines/files, etc etc.. In the meantime, for heavy column work and other tasks that require stuff in the aforementioned list I use another editor - Crisp in my case. If your workflow is primarily column orientated, Sublime is probably not the best choice. And nearly every coder and hacker I know who uses Sublime has another editor to fall back on for such things.

Though I love Sublime for general coding work, it's not the perfect editor for all types of text editing. I'd love it to be so, but we'd need to see the pace of development pick up for that, or for Sublime to be open-sourced. I doubt that either will happen any time soon, though I'd happily be proven wrong.